Spero Therapeutics and GSK Reveal Phase 3 Results for Tebipenem HBr

Spero Therapeutics, Inc. and GSK plc announced promising results from the pivotal Phase 3 PIVOT-PO trial, which evaluated the efficacy and safety of tebipenem HBr, an investigational oral treatment for complicated urinary tract infections (cUTIs), including pyelonephritis. These findings were presented on October 20, 2025, during a late-breaking oral abstract session at IDWeek 2025 in Atlanta, Georgia.

The PIVOT-PO trial focused on assessing tebipenem HBr as a potential first oral carbapenem antibiotic for the treatment of cUTIs. A significant need exists for effective oral therapies in this area, as current options often require intravenous administration. According to data shared by the companies, tebipenem HBr demonstrated a favorable efficacy profile, which could change treatment paradigms for patients suffering from these infections.

Trial Highlights and Results

The study involved a diverse patient population, with robust metrics indicating the drug’s effectiveness in treating cUTIs. The trial’s primary endpoint was met, showing a statistically significant improvement in clinical cure rates compared to the placebo group. Specific figures revealed that tebipenem HBr achieved a clinical success rate of approximately 87% in patients, which is a substantial improvement over standard therapies.

Safety assessments also indicated that tebipenem HBr was well-tolerated, with adverse events comparable to those observed in the placebo group. Notably, GSK and Spero Therapeutics emphasized the importance of these findings, as they suggest that tebipenem HBr could provide an effective oral option for patients who may otherwise face challenges with intravenous antibiotics.

The trial, registered under NCT06059846, enrolled participants from multiple sites, enhancing the robustness of the results. The findings are especially relevant given the increasing prevalence of antibiotic-resistant bacteria, making the need for novel oral treatments critical.

Future Implications

With these promising results, Spero Therapeutics and GSK are now preparing to engage with regulatory authorities to discuss the potential for expedited approval of tebipenem HBr. If approved, this medication could represent a significant advancement in the management of cUTIs, providing healthcare professionals with a new tool to combat these complex infections effectively.

The companies are optimistic about the implications of their findings and are committed to further research that supports the development of tebipenem HBr. As antibiotic resistance continues to pose a significant threat to public health, innovative solutions like this are essential to ensure effective treatment options remain available for patients worldwide.

The presentation at IDWeek 2025 marks a critical step forward in the ongoing fight against cUTIs and highlights the collaborative efforts of Spero Therapeutics and GSK to address unmet medical needs in this domain.